Health & Safety: Low risk environments: To PAT or oPAC?

The law requires employers to assess health and safety risks and take appropriate action to maintain electrical equipment if it can cause danger, however, it does not stipulate how or when. HSE has published new guidance to help businesses based in low-risk environments (eg. offices and shops) maintain their portable appliances more cost effectively. This factsheet is a quick reference to hopefully save you some time checking you are up to date with the latest help on the how and when.

What is PAT?

PAT: Stands for Portable Appliance Test/ing
A Portable Appliance: Is any electrical equipment which can be moved for use in different locations. A most obvious portable appliance is a floor cleaner but also included are large items such as photocopiers and vending machines and, on the flip side, extension leads and battery charging equipment.
The Test: Checks for electrical evidence that the appliance may not be safe to use. It must be completed with the correct testing equipment by someone who knows how to use it and how to interpret the results (an electrician is not necessary).

HSE advises that not every item needs a PAT and that some items may be sufficiently maintained with other portable appliance checks (I\’m calling these oPAC for short). PAT only gives an indication of possible faults inside an appliance so oPAC are also required for all PAT items too.

What are oPAC?

oPAC: other Portable Appliance Checks; HSE identify two types: user checks and formal checks

User (Employee) Checks: Looks for exterior physical evidence that the equipment may not be safe to use. Employees are to be encouraged to carry out these checks before equipment is used (the equipment should be disconnected).

Indications that the appliance is not safe to use and requires maintenance:

  • Fraying, cuts or heavy scuffing on the lead or the lead trapped under furniture or in floor boxes
  • Damage to the plug cover or bent pins
  • Coloured wires visible where the lead enters the plug or tape applied to join leads together
  • Damage to the outer cover of the equipment itself, including loose parts or screws
  • Signs of overheating; burn marks or staining on the plug wires or cover of the equipment
  • Signs that the equipment that has been used or stored in unsuitable conditions, such as wet or dusty environments or where water spills are possible

Formal (Visual) Checks: Looks at fitness for purpose as well as double-checking the user checks and, where possible, inspecting inside the plug for evidence that the equipment may not be safe to use. It must be performed by someone with sufficient knowledge to avoid danger to themselves or others (an electrician is not necessary).


  • The user checks above should be repeated, has the user reported any issues?
  • Is the equipment being used correctly and in an appropriate environment (in accordance with the manufacturer\’s instructions) and is it suitable and safe for the job
  • Inside the plug check that:
    • There are no signs of internal damage, overheating or water damage
    • The correct fuse is in use (in moulded plugs this is the only check that can be made)
    • The wires are attached to the correct terminals and the terminal screws are tight
    • The cord grip is holding the outer part of the cable tightly and there is no bare wire visible other than at the terminals

Who is responsible for PAT & oPAC?

You are responsible for: equipment you or your employees supply for use by your employees at work
You have joint responsibility for: equipment leased or provided by a contractor for use by your employees
You are not responsible for: equipment both provided and used by a contractor

When does PAT or oPAC need to be done?

Checks should be done periodically to ensure unsafe portable appliances are not being used. You should decide the level of maintenance needed according to the risk of an item becoming faulty, and how the equipment is constructed (if it is earthed or doubled insulated). The table below shows the suggested checks to make and initial intervals between checks for types of equipment as given by the new HSE guidance. You may notice over time, from the amount of problems being found, that the tests are required less, or more often.

Battery operated or less than 50volts AC eg. telephone equip. and low voltage desk lamps: No tests required. Not handheld items rarely or occasionally used eg. fans, computers, photocopiers and vending machines: Formal visual checks every 2-4years and Class I(Earthed) items combined oPAC and PAT tests up to every 5 years. Handheld equipment more than 50volts AC eg. kettles, irons and floor cleaners: User checks, formal visual checks every 6months-1year and Class I items combined oPAC and PAT tests every 1-2years. Leads and plugs connected to the above and battery charging equipment eg. cables, mains voltage extension leads and battery chargers: User checks, formal visual checks every 6months-4years based on equipment connected to it and both Class I and Class II items combined oPAC and PAT tests every 1-5years based on equipment connected to it.

For the full HSE guidance booklet:

Factsheet: H&S- Low risk environments: To PAT or oPAC?
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